This proposed CAPRISA Mucosal Immunology mucosal biomarkers training grant, focusing on utility of omics approaches for biomarker discovery, seeks to extend and advance understanding of biological predictors for HIV transmission through building in-country systems biology capacity. This objective strongly aligns with the broader goal of designing better biomedical tools to prevent HIV acquisition, particularly in young women, who remain disproportionately affected in Southern Africa and beyond. The CAPRISA Mucosal Immunology Laboratory through the Columbia University-Southern African Fogarty AIDS training Program has developed substantial in-country expertise in measuring and characterizing immune cells and cytokines, key mediators of inflammation at mucosal sites. Building the in-country systems biology capacity of this laboratory will fill a critical research training and capacity gap in the team. Systems biology approaches, applied in the context of the immune system, contributes to deeper insight into the complexity and interconnectivity of host protection thereby advancing understanding of HIV susceptibility and protection. In-country mentorship of early to mid- career level scientists will be supplemented with training opportunities with existing and new collaborators in the USA in the field of systems biology that will be utilized to transfer this technology and analyses platforms to the CAPRISA Mucosal Immunology Laboratory Staff in Durban, South Africa. The planning grant will be utilized to strengthen existing and establish key new collaborative partnerships that fill important gaps in capacity through a formal structure to support the future research training program; review current resources at CAPRISA and justify the need for to bring the CAPRISA Mucosal Immunology Laboratory to the next level of capacity to advance research in correlates of HIV risk; to identify potential trainees for future research training and review existing and future research opportunities to support research training and career development of trainees. These activities will be utilized to develop and submit an application in response to the related D43 FOA.